C5 brake upgrade question...conversion bracket
 

Does anyone happen to know how thick the conversion brackets are for a C5 brake setup? My caliper bracket isn't centered over my rotor, and the only thing I can think of, is my conversion bracket is too thick. When I put washers between the hub and spindle, pushing the rotor itself outward 1/8", the calipers bracket centers up perfectly. My current conversion brackets measure 1/2", should/could they be thinner? If they were 3/8", they'd work perfect.

Re: C5 brake upgrade question...conversion bracket
 

Strange. 1/2" is correct for a stock spindle with stock offset hub. You are using the C5 12.8" rotor, right? Make sure there there is nothing preventing all the parts from mating correctly.

Do you have pictures, it might help spot something.

Worst thing you could get a custom set of brackets made or you could reduce the thickness of the bracket in the mounting hole area with a counterbore or similar.

John

Re: C5 brake upgrade question...conversion bracket
 

Yeah, just read 1/2" on a post from here myself. It's a C5 rotor, and I don't recall anything preventing the parts from going together well. Thats kinda why I was a little confused. The conversion bracket is the only thing between the spindle and caliper bracket, so I had assumed that was the issue.

I'm rebuilding the calipers and making everything pretty before I put it all back together. Guess I'll post some pics when I get everything together to further address the issue.

Yeah, I was thinking about a custom bracket or having a machine shop thin the brackets slightly around the spindle mount area. If it needed to be done, a 3/8" bracket would be strong enough, right?

Re: C5 brake upgrade question...conversion bracket
 

3/8" is generally fine. Do you have a picture of the bracket, I just want to make sure the design is good before committing to 3/8".

John

Re: C5 brake upgrade question...conversion bracket
 

Check if the bracket sits level with the rotor. I have had spindles where I had to face the bosses or the holes down, the bracket sat a little crooked. Must be some tolerance in the fabrication of these things. It's real soft material, a hand file wil take it down. Easiest way to check if it's flush is to bolt on the rotor and measure from bracket to rotor inside face. The side that's off, remove the bolt, then slide the bracket away and snug up the other bolt. Slide it back and it will hit the boss. Take off material with a sharp flat file and keep rotating the bracket and checking to see if it slides over the boss. May take a few tries but you will get there. It only takes a little bit of tolerance for the abutment bracket to be rubbing the rotor or not sitting centered over the rotor

Re: C5 brake upgrade question...conversion bracket
 

Thank you...now that I think about it, I do believe the holes in the bracket were a touch off. If one bolt was tightened all the way, the other didn't fit directly over the hole in the spindle. I had to loosen the bolt to get the other bolt to thread, so it couln't have sat flush. I planned to file it down, but didn't realize it was keeping the bracket from mounting totally flush with the spindle. :crazy: Turns out something was preventing them from mating correctly. ha I'll file the bracket holes and see if that works, I'm betting it will. It's too simple and makes too much sense, not to be the problem. Thanks a lot fellas, much appreciated. I'll let you know if that doesn't work.

Re: C5 brake upgrade question...conversion bracket
 

Worked a little on this last night, and indeed the bracket was crooked. More than I would have thought really. I took the material off the high side with a file, and the bracket fits much better now. Thought I'd have to file the holes in the bracket bigger, but now that the bracket sits level on the spindle, the holes line up perfectly.

Still want to file the spindle down just a touch more to center the bracket over the rotor, but my problem has been solved. Thanks again for the advice. :thumbsup:

Re: C5 brake upgrade question...conversion bracket
 

You are saying the bracket is bent? That is very strange as it is thick steel. I don't see how it would be bent by accident unless the material was already bent before the bracket was made.

I would avoid filing on the spindle if you can help it, as it will just cause frustration if you ever want to change brakes again. But used spindles are cheap, so no big deal I guess.

John

Re: C5 brake upgrade question...conversion bracket
 

Not bent, the bracket was resting crooked against the spindle when I first put it together. Once I filed down the high side of the spindle, as Twin_Turbo suggested, it rested flat against the spindle and everything lined up correctly. Prior to that, I was just barely off the second hole, with one side tightened all the way. I wasn't comfortable really tightening everything since it didn't line up the way I would have liked. Once the bracket rested flush on the spindle, it moved everything back a bit. Almost exactly where I want it, but a touch too close to the inside of the rotor.

I thought about the spindles if I ever changed my brakes, but if everything else is what it should be, in terms of thickness and dimensions, I was hoping switching would be simple. In theory, if my brackets are correct, it should work...possibly. ha Of course, things rarely are and as you said, used spindles are cheap. I'm less than a 16th off, but I would really like the abutment bracket centered over the rotor perfectly.

Re: C5 brake upgrade question...conversion bracket
 

I'm filing down the contact area between the conversion bracket and spindle, on the spindle side. Seems plenty thick and with a file I'm not taking off all that much quickly. They were actually powdercoated spindles, so I had already sanded down/off the powdercoat. Just need to remove a touch more material, not much at all, to be perfectly centered with my bracket over the rotor.

Re: C5 brake upgrade question...conversion bracket
 

I have had more than 1 of these spindles having this issue that the bosses for the bolts are not level. OEM not a problem since it's just holding a rock shield but the adapter brackets will sit crooked if you don't face down the higher spot.

Re: C5 brake upgrade question...conversion bracket
 

funny, I was gonna ask if they were for the shield. That would explain the sloppy tolerance.

Re: C5 brake upgrade question...conversion bracket
 

Yup, got it. I'm still not a fan of doing it with a file because how can you be certain you are filing perpendicular to the spindle snout? Realistically you should be fine, I'm just a stickler for that kind of stuff.

Re: C5 brake upgrade question...conversion bracket
 

hey...sometimes you have to forget about the finicky stuff and just get it done LOL

Re: C5 brake upgrade question...conversion bracket
 

The areas I'm filing down cover about one square inch. I'll be able to keep it level enough to rest a bracket on it that is less than a foot long. As long as I can get the brackets on flush/square, secure, and centered over the rotor, I should be just fine. I'm a stickler as well, if I didn't think i could do it correctly i wouldn't even attempt it. I've seen some of the things people do to their cars on these boards, so I suppose your concern is somewhat warranted. HA

Re: C5 brake upgrade question...conversion bracket
 

I am sure you will be fine. I setup and shim each spindle perpendicular to my drill press before drilling and taping the dust shield holes. For your situation, I would probably do the same thing but then chuck a larger end mill and use that to shave down the boss. That would insure the boss is straight, level, and cut to a specific height. Just something to think about for the future.

http://farm9.staticflickr.com/8463/8...a426af4f_h.jpg

Re: C5 brake upgrade question...conversion bracket
 

I sent my spindles out and got exchanged another set of spindles, because I was afraid I might tap a hole a little crooked. The use of a setup like that, would be the only way I'd drill/tap a spindle myself. If I had access to a drill press like that, I'd likely do what you explained and shave down the boss perfectly level. Much quicker and if you have the right tool for the job, why not use it right? I do however....own a set of files. HA

Re: C5 brake upgrade question...conversion bracket
 

I had this same problem when I did my swap. The guy that sold the adapter plates to me at the time said that some spindles had to use the washer. So he mailed me a washer and they have worked fine for about three years now.